On Monday 30 March 2020 21:52:42 andrew beck wrote: > hey guys I was asking about connecting a 12v mpg encoder to my mesa > 7i76 card. last week. I have done some testing with a pc atx power > supply and a multimeter and it looks like at 12 v when measuring > between the A channel and ground(0V) the high value is 5.2 volts and > low is zero(or close to it) also there are some nice status leds that > show what the channels on the mpg are doing. > > when powering it with 5 volts the leds don't work and the high voltage > is 2.7 volts and the low is zero volts. I read the threshold in the > mpg inputs is 2.5 volts with 10 percent hysteresis so I need to pull > at least 2.8 volts. also I am thinking that might be a bit close and > result is unreliable operation. > > Is there anyway I can supply this with 12 volts from my board? I am > running the field voltage at 24volts. > > regards
See if any ebay vendor on this side of the pond (for quick delivery) has a stock of 3 to 5 dollar "buck" regulators. Some even come with a voltmeter display you can turn off once its set. Common negative, but you can put your 24 into one end, and get an adjustable from below 5 to a couple volts below the 24 out of the other end. I've used 5 or 6 of them for several years, one failure, but it failed short and fried a $20 bob it was making 5 volts for. I think they can handle a 2 amp load. Functioning in switch mode, they don't make much heat. > Andrew > > On Tue, Mar 24, 2020 at 7:53 AM Peter C. Wallace <[email protected]> wrote: > > On Tue, 24 Mar 2020, andrew beck wrote: > > > Date: Tue, 24 Mar 2020 07:34:01 +1300 > > > From: andrew beck <[email protected]> > > > Reply-To: "Enhanced Machine Controller (EMC)" > > > <[email protected]> > > > To: "Enhanced Machine Controller (EMC)" > > > <[email protected] > > > > > > Subject: Re: [Emc-users] connecting up mpg > > > > > > Hey Peter. > > > > > > When I enable the mpg mode does that mean I will lose my whole > > > config or > > > > do > > > > > I just need to change something in the Hal file. > > > > YOU just change some settings in the hal file > > > > > I'm thinking It sounds like the best thing is to setup all my io > > > in pnfconfig leaving the mpg inputs spare and then after that > > > start hard coding in Hal. > > > > Yes leave the 2 or 4 pins (for 1 or 2 MPGs) free if you want to use > > a MPG Note the enabling the MPG in the hal file will not cause you > > to lose the ability > > to use inputs 16..19 for normal digital input use > > > > > Do you know how much I can do in pnfconfig? > > > > I dont think pncconf supports MPG setup, so this needs to be done by > > editing the > > HAL file > > > > > New Zealand is going in to total isolation for a month from > > > tomorrow because of covid 19 so I have some time for this lol :) > > > > > > Regards > > > > > > Andrew > > > > > > Regards > > > > > > Andrew > > > > > > On Mar 24, 2020 3:18 AM, "Peter C. Wallace" <[email protected]> > > > wrote: > > > > > > On Mon, 23 Mar 2020, andrew beck wrote: > > >> Date: Mon, 23 Mar 2020 17:32:56 +1300 > > >> From: andrew beck <[email protected]> > > >> Reply-To: "Enhanced Machine Controller (EMC)" > > >> <[email protected]> > > >> To: "Enhanced Machine Controller (EMC)" < > > > > [email protected]> > > > > >> Subject: [Emc-users] connecting up mpg > > >> > > >> > > >> Hey guys. > > >> > > >> I have a 12 volt mpg > > >> > > >> I want to connect it to the 7i76 board. do you know if I can > > >> connect it straight up. I think that the mesa boards only want 5 > > >> v and I am not > > > > sure > > > > >> how to connect up my 12 volt mpg > > > > https://drive.google.com/file/d/1uOF2y7KFSchXLhQ3s79GSB1x_WZieQ5l/vi > >ew?usp=sharing > > > > >> I did a bunch of searches on the forum but couldn't get a > > >> definite > > > > answer. > > > > >> I tried to attach a photo but it bounced back. so here is a link > > >> > > >> regards > > > > > > You can connect a 12V MPG to the 7I76 MPG inputs (field inputs > > > 16..19), > > > > but > > > > > not > > > the high speed encoder input. Note that the input threshold for > > > MPG > > > > inputs > > > > > is > > > 2.5V so the MPG output needs to swing close to ground for reliable > > > > operation > > > > >> < > > > > https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm > >_campaign=sig-email&utm_content=webmail > > > > >> Virus-free. > > >> www.avast.com > > >> < > > > > https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm > >_campaign=sig-email&utm_content=webmail > > > > >> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> > > >> > > >> _______________________________________________ > > >> Emc-users mailing list > > >> [email protected] > > >> https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > Peter Wallace > > > Mesa Electronics > > > > > > (\__/) > > > (='.'=) This is Bunny. Copy and paste bunny into your > > > (")_(") signature to help him gain world domination. > > > > > > > > > > > > > > > _______________________________________________ > > > Emc-users mailing list > > > [email protected] > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > _______________________________________________ > > > Emc-users mailing list > > > [email protected] > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > Peter Wallace > > Mesa Electronics > > > > (\__/) > > (='.'=) This is Bunny. Copy and paste bunny into your > > (")_(") signature to help him gain world domination. > > > > > > > > _______________________________________________ > > Emc-users mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-users > > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
